The invention relates to containers for storage, transport and use of liquid chemicals including acids, solvents, bases, photoresists, dopants, inorganic, organic, biological solutions, pharmaceuticals, and radioactive chemicals. In particular, the invention relates to a coupling member mounted within a mouth of a container which permits fluid to be drawn out of and recirculated into the container at the same time through the mouth of the container.
During the shipment of liquid chemicals and high purity fluids, vibration of the shipping container creates contaminating particles within the fluids which lower the purity of the fluids and prevent the ultimate use of the high purity fluids and liquid chemicals once delivered. As a result, it is often necessary to test the high purity fluids for contamination and to filter the high purity fluids to remove the contaminating particles and to re-establish purity. Thus, the liquid chemical or high purity fluids must be withdrawn from the container, tested and/or filtered, and then recirculated back into the container.
Typically, the recirculation of the high purity fluids requires a specialized container having at least two ports or mouths in communication with the interior of the container. Unfiltered or untested fluid is withdrawn out of one of the ports while filtered or tested fluid is recirculated back into the container through the second port. Because recirculation of the fluids requires a specialized container having two ports, recirculation or testing is expensive. In addition, the structural integrity of the container is often impaired by the need for a second additional mouth or port into the container. Moreover, because recirculation has typically required two ports into the interior of the container, container systems employing flexible bags or film pouches within an outer bottle or overpack are not suitable for recirculating fluids for testing or filtering because the flexible film pouch generally includes only a single port.